Article: Sugar and Diabetes
Author: Carol Browne is an International Consultant Nutritionist, working on nutrition education projects in Africa for agencies of the United Nations. Carol has consulted to the South African Department of Health on many occasions, most recently to develop a training package on complementary feeding. She is registered with the Health Professions Council of South Africa as a nutritionist.
Article appeared in: South African Sugar Journal. November 2015.
The links between nutrition, food and health have been made for centuries; some of the early links were later found to be based on scientific fact.
The consumption of limes by sailors to prevent scurvy is an example, with a deficiency vitamin C being shown to cause scurvy centuries later, in 1932. Regrettably misinformation about many aspects of nutrition, food and health prosper, and misinformation about sugar falls on fertile ground when discussed by many in the nutrition arena.
The topic of sugar consumption and diabetes has two parts; the first being whether or not eating sugar causes diabetes and the second is whether or not people with diabetes can eat sugar. An understanding of the current increase in the magnitude of the debate about sugar (and other aspects of diet and lifestyle) and diabetes also warrants attention.
What is Diabetes?
Diabetes is a condition that affects the way a person’s body uses blood glucose (blood sugar). Diabetes cannot be cured, but it can be managed through diet, lifestyle and medication. Type 1 diabetes is diagnosed when a person has no insulin produced in their body. The reason for this occurring is not known, it may start in early infancy or later in life. Type 2 diabetes is characterised by a gradual decrease in the effectiveness of the action of insulin. Type 2 diabetes used to occur in older people, but is now found in children and adolescents, especially when they are obese and inactive.
Insulin is a hormone, normally produced in the pancreas in response to elevated blood sugar levels, such as after eating meal with carbohydrate containing foods. People with undiagnosed diabetes will have high blood sugar levels, as insulin has not moved the sugar from the blood to the muscles or to storage. But they will have a shortage of glucose in their organs and muscles, as insulin has not transported the glucose from the blood to the sites where it is needed.
The use of Sugar in Healthy Eating Plans for People with Diabetes.
The management of diabetes aims to achieve and maintain blood glucose levels within healthy ranges. Decades ago it was believed that refined sugar and products made with refined sugar would cause blood sugar levels to rise rapidly and then fall rapidly. This was contrary to the objective of disease management, and hence people diagnosed with diabetes were told not to eat refined sugar, and foods made with refined sugar.
In the 1980s scientists tested the body’s response to sugar consumption by taking measurements of blood glucose, at frequent intervals, after research subjects ate it in a controlled situation. Many other carbohydrate containing foods were also tested, and ironically it was found that some foods with starch (complex carbohydrates) caused a more rapid blood glucose response than did refined sugar.
This information has slowly been incorporated into advice given to people with diabetes about healthy eating. Commenting on this Professor Corinna Walsh, of the University of the Free State “A large body of evidence confirms that limited amounts of sugar can be used by persons with diabetes without any negative effects on blood glucose control. Despite this, many people still believe that sugar should not be included in the diet of people with diabetes.”
Does Eating Sugar Cause Diabetes?
The reason why many people think that eating sugar causes diabetes is probably linked to this historical diet advice. It may also be due to the colloquial name for diabetes mellitus, which is ‘blood sugar’ or possibly explained as ‘too much sugar in the blood’.
There is no evidence that refined sugar has any unique attributes that result in the development of diabetes.
The Links Between Diet and Lifestyle and Diabetes.
Globally, energy from meat, sugars, oils and fats has been increasing in recent decades. Simultaneously the consumption of foods such as whole grains, legumes and fresh vegetables has declined. This substitution of nutrient dense, fibre rich, minimally processed foods of plant origin with processed and fast foods has led to an increase in non-communicable diseases.
This recent eating plan, combined with a decrease in activity, is associated with increasing prevalence of overweight and obesity, elevated blood pressure and blood cholesterol and resistance to the action of insulin. These conditions are risk factors for the development of disease, including diabetes.
An increase in sugar consumption is often part of this change that has occurred in diet and lifestyle patterns, and in disease patterns. When a person eats more food than they need they are at risk for weight gain; if sugar is the food that is tipping the scale from enough energy to excess energy, then high sugar uses will gain weight. This excess weight will put them at risk for developing diabetes and other diseases.
Sugar, as part of a healthy eating plan and healthy lifestyle, can be enjoyed without risk to health.